A good move, since the rook is useful on the third rank. There are options of equal value, the position of a \"slow\" character, meaning that many plans are possible.
10... e7g6  11. f1e1  11... h7h6 Gukesh is preparing Nh7-g5, exchanging a pair of knights. The computer suggests another plan: 12. d3d4  12... f6h7 